JPRS ID: 9264 USSR REPORT PHYSICS AND MATHEMATICS

Document Type: 
Collection: 
Document Number (FOIA) /ESDN (CREST): 
CIA-RDP82-00850R000300020036-7
Release Decision: 
RIF
Original Classification: 
U
Document Page Count: 
112
Document Creation Date: 
November 1, 2016
Sequence Number: 
36
Case Number: 
Content Type: 
REPORTS
File: 
AttachmentSize
PDF icon CIA-RDP82-00850R000300020036-7.pdf6.05 MB
Body: 
APPROVE~ FOR RELEASE: 2007/02/08: CIA-R~P82-00850R000300020036-7 , ~ ~ ~ ~ ~1~1~~~T ~~a~ ~ ~~L~~ . ~ ~ ~ APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 i~~?it t~i~r~c t-~i. i ti~ ~~ti~.~ - JPRS L/9?_6~ 21 August 1980 - USSR Re ort p PHYSICS AND MATHEMATICS CFOUO 7/80) FB~$ FOREIGN BROADCAST INFORMATION SERVICE FOR OFFICIAL USE ONLY ~ APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 NOTE JPRS publications contain information primarily from foreign newspapers, periodicals and books, but also from news agency transmissions and broadcasts. l~iaterials from f.oreign-language sources are translated; those from English-language sources are transcribed or reprinted, with the original phrasing and other characteristics retained. Y Headlines, editorial reports, and material enclosed in brackets - [J are supplied by JPRS. Processing indicato-rs such as [Text] or [Excerpt] in the fi.rst line of each item, or following the last line ~f a brief, indicate how the original information was processed. Where no pr~cessing indicator is given, the infor- = mation was summarized or extracted. Unfamiliar names rendered phonetically or transliterated are enclosed in parentheses. Words or na~es preceded by a ques- tion mark and enclosed in parentheses were not clear in the original but have been supplied as appropriate in context. Other unattributed parenthetical notes within the body of an item originate with the source. Times within items are as - given by source. The contents of this publication in no way represent the poli- - cies, vi.ews or attitudes of the U.S. Government. For farther information on report content _ call (703) 351-2938 (economic); 346�i (political, sociological, military); 2726 (life sciences); 'L725 (phys~cal sciences). COPYRIGkT LAWS AND REGULATIQNS GOVERNING OWNERSHIP OF MATERIALS REPRODUCED HEREIN R~'QUIRE THAT DISSEMINATION OF THIS PUBLICATION BE RESTRICTED rOR OFFICIAL liSE 0~]LY. APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 F'OR OFFICIAL U3E ONLY JPRS L/9264 = 21 August 1980 USSR REPORT PHYSICS AND MATHEMATICS (FOUO 7/so) CONTENTS ELECTRICITY AND MAGNETISM A Study of a Long Sliding Spark 1 High-Current Coaxial Discharge in the Air Stabilized by a Dielectric Wall 7 FLUID DYNAMICS Abstracts on Inhomogeneous Fluid Dynamics 14 LASERS AND MASERS Active Media of Exciplex Lasers (Survey) 18 A Closed-Cycle Gasdynamic C02 Laser With Gas Separator............ 79 Prospects for Using an AC Discharge to Pump Fast-Flow Closed-Cycle Carbon Dioxide Technological Lasers 86 Spatial Coherence of Emission of a Laser With a Resonator That Is Filled With a Randomly Inhomogeneous Medium 93 . A Pulse-Periodic Excimer Laser 97 ~ NUCLEAR PHYSICS LIU-10 High-Power Electron Accelerator 101 - a - [ I I I US S R- 21H S&T FOUO ] ~ FOR OF~ICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 FOR OFFICIAL USE ONLY - ELECTRICITY AND MAGNETISM UDC 533.09 A STUDY OF A LONG SLTDTNG SPARK _ , Novosit~irsk ZHURNAL PRTKLADNOY MEKHANTKT T TEKHNICHESKOY FIZIKI in Russian No 1, Jan-Feb 80 pp 111-115 manuscript received 14 Dec 78 - [Pager by S.I. Andreyev, Ye.A. Tobov, A.N. Sidorov and V.D. Kostousov, LeningradJ [Text] The flashover characteristics of sliding sparks up to 2.5 m long are stud3ed for various gases at different pressures. Studies of sliding sparks in a~r at atmoapher~c pressure are - described in the literature j1, 2]. Th~: studies in this work _ were carried out fn argon, neon, heii~um and a~r at pressures of from lU to 1,600 mm Iig. The sliding d~sct~arge took piace at the surface of a dielectric film wit~cfl ~ras enveioped by a metal tube connected to one of ~he electrodes ('tl~e so-called "~r:~t~ator"). The diameter of the init~ator was 40 mm. The - film thickness was 0.4 fio 4 mm. The length of the discharge gap varied from 0.25 to 2.5 m. The discharge was realized in a dielectric chamber 450 mmi in diam~eter which was evacuated and then filled with various gases. A cable transformer served as the voltage source ~1, 2]. The voltage across the secondary winding had the form of a decaqing cosinusoiu at a frequency of from 30 to 120 I~z. The logarithmic decrement of the attenuation was 10-2. - The experini,~ntaZ resuZts. The breakdown voltage 1eve1, UPr, was studied in all of the experiments. This quantitp was defined as the lowest amplitude at which the sliding spark bridges the discfiarge gap. The influence of the dielectric film thickness, ~~3n mm), can be expressed in terms of the specific f3.lm capacitance, Cud = 0.88 e/~, of which the - breakdown voltage is a unique function. The function Upr (Cud) is shown in Figure 1 for argon, neon, helium and air - (curves 1- 4 respectively), plotted f~r gap length of Z= 1 m at 1 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 rVt( vrr~~..ciL uJ~ U1VLY X U~F.KB ~ (A) - f20 U~P , KB~, 3 ~ ' x x B0 3� 80 ~ ~X\ 2 x\x 40 \ ~x~_x_" 4 40 2' 1 ~x X_'_"~x- 3 `x f ~X`X K X_ ' ' . J 0 4 8 /2 /6 20 24 i CYA , n4~/cr~? (g~ O '=0 200 L~ eM Figure 1. ~ Figure 2. Key: A. Upr [breakdown voltage] , KV; Key: A. Breakdown voltage, KV. _ B. Cud [specific capacitance], picofarads/cm2. atmospheric pressure. It can be seen that with an increase in C~d, U r falls off rapidly at first. But starting at Cud = 2 to 5 pFd/cm , the change 3n UPr becomes minar. Tt is physicaily poss~ble to explain this by the fact that the increase in Cud initially leads to a rise in the capaci- tive current, and conseqnently, in the overall current through the uncom- pleted discharge channel. The yrise in the current leads to a reduction in the channel resistance and the effective ~ransf.er o~ the h~gh voltage elec- trode potential (fram which the s1~d~ng d~scharge deveiops) to the head of the uncompleted leader channel. Th~s potent~al prov~des for the occurrence of ionization processes at the head and fihe deve7,opment of iche leader. With a sufficiently high value of Cud, the growfih in the potential at the head experiences saturation. It can also�be seen from the data of Figure 1 that the ratio of the break- ~ down voltages for the various gases depends slightly on the quantity Cud at rather high values of Cud. This can likewise be explained by the decisive influence of ionization proces ses at the head of the uncompleted leader channel. The processes are bas ically determined by the area in front of the head, in which the multiplicat ion of the electron awalanches and streamers takes place. UPr is shown in F3gure 2 as a funct~on of the length of the discharge gap Z for argon (1 and 1F), neon (2 and 2F) and helium (3 and 3~) for values of Cud of 1.6 (curves l- 3) and 3.0 pFd/cm2 (i~ - 3f). As was noted earlier, an inflec t~on point was observed ~,n the curve for Upr(Z) for the case of a~r j2]. For values of Z= Z~r, the voltage increas- es pract~cally linearly as a function of Z(tRe f~e1d intensity in the sec- tion of the channel from Z~r to Z remains constant). Tt turned out that the point of inflection (Z~r,'Ucr) is determined ~at least in the range studied here) only by the quantity Cud and the kih~ of gas (at an initial pressure 2 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 FOR OFFIGIAL USE ONLY of p> 200 mm Hg) and does not d epend ~~6 on p: 3 soj ~A) . ~ U~r = ACua'S, KV; Z~r = BCud' S, m. ~ 2 ~ The constants are A= 80 and B= 1.15 6 J 3~ for helium; A= 54 and B= Oo75 for ' neon; A= 17.2, B= 0.75 for argon. ~0 . The values of the constant field in- tensities in the region above Z~r are 0 200 4~ao r2a~ ~aoo ~60o as fol2ows: Epr = 14.5 KV/m for heliim p~, MM p~. c~ 8.3 KV/m for neon and 4. S KV/m for argon. Figure 3. When Z> Z~r, the breakdown volt age can be determ~ned from the formula: Key. B: P~reak~do g,voltage, KV; ~1~ Up~ _~.1[U~r +.EPr(Z - Z~r)], KV. The given values for Ucr~ Zcr ar~d Ep.~, make it possible to determine UP r using (1) with an error of around 10%. Upr ~s shoWn ~n F~gure 3 as a func- tion of tcte gas pressure. Ih contrast to tlte Paschen curves, the pressure does not influence UPr ~Ln a w3de range jof pre~~res]. Curves 1 and 1' were obtained for argon, 2 and 2~' were obta~ned for neon, 3 and 3' for hel- - ~um; curves 1- 3 apply to the case of a f:tlvi t11~cRness of p= 2 mm (Cud - = 1.6 pFd/cm2) for a length of 2 m, whi7,e - 3~ are for 4= Q.5 mm (Cud = 3 pFd/cm2) for a length ot 0.5 m. The fact that the gas pressure does not influence the development of a leader in a wide range of pressures is ev~dence that ~ the case considered here, the quantity E/p (E is the field intens~ty at tt~e head), whi~h deter- , mines the intensity of the ionization processes at a given point in the gas, does not exert any substant~21 influence on fihe development of a leader. At the same time, the influence of Cud is manifest when the press- ure p changes (see Figure 3). Tt can be concluded as a result that the de- velopment of a leader is primarily determined by the overall current which flows i,nto its head, while th3s quantity is in turn determined by the area over which the�ionization processes take place. The intensitp of these pro- cesses practically remains constant, since in the electrical field reg ion at the head, there exists a large o�vervoltage and a change in E/p with a change ~n p under the conditions considered here does not increase the cur- rent feeding the leader head, wiz~le the area wz:th tl~e effective ion~zation does not c~qnge in this case (it ~s determined by tlie geometry of the uni- que capacitor formed by the conducting rod lying above the conducting plane). - In the range of comparatively low pressures, a leader apparently develope, without substantial overvoltages at the head. For this reason, a change in p leads to a change in the intensity of the ioniz~tion processes and to a change in the current collecting surface in front of the head. 3 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007/02108: CIA-RDP82-00850R000300020036-7 FOR "�x r' L~:1 AL USE ONLY ~ It is interesting that in such an electronegative gas as air, i.n contrast to the inert gases, the influence of pressure is marked throughout the en- tire range investigated from 37 to 80~ mm Hg (Figure G), if Z> Z~r (curves 1 and 2 apply to a discharge gap 1en~th of Z= 1.9 m where Z~r = 1.08 m and 0.79 m respectively). Tn the case of a short discharge gap, Z< Z~r ( cur- ves 3 and 4 were obtained where Z= 0.35 m and with the same values of Zcr~~ the influence of pressure fa11s off. (t~l , u~P,ne _ ~zo . ~P U~r f ~ - ~ gp 80 � ~ 3 60 ~ " ~p , - i~ 30 ~B) - . -r -----r ----T-r--T-T---- m l~t 0 ?c,"J dC~ EDOpo~�Mpr.cr. ,0 OS f0 1S ~ ~ , Figure 4. Figure 5. Key: A. Breakdown voltage, KV; B. Po~ ~ Hg. _ We will note that in the case of air where Z> Z~r, the rise in the break- down voltage with a rise i~~ the pressure takes place linearly with a cons- ~ tant of 0.014 KV/mm Hg where p~ 200 mm Hg. The dynamics of the pracess of - slip dis~harge development [1] should also be brought into P1ay to explain the data of Figure 4, which sfiow the differ3ng influence of p for short, Z< L~r, and 1ong, Z>~.~r, gaps. - ~ Studies have shown that the breakdown in argon differs from the br~akdown - in other gases with a fast rate of leader channel development in the ~ d~scharge gap; the breakdown ~i a11. of tfle cases studied here occurred over the time of the voltage rise. Tn the case of helium, ne6n ~nd air, the average rate of leader channel development is slower than ~.n argon, and when 2> Z~r, the development of the flahsnver encompasses a region of voltage which changes sharpiy with time. IY? this case, the developmenfi taltes place 3n a nonuniform - fashi.on j1]. Characteristic stoppages and even "~ext3mction10 0� ~he channel ~~:.ur during the develo~men~, where these are determined both by the a~so7.ute 7.eve1 of the instar~taneous voltage and its t~ne derivative. This exp7.ains t.I~e multiplicity of glashover characterist~'`es of a sliding spark Frh~ch are found in the literature j3 ~ 8]~ 4 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000300024436-7 FOR ~FFICIAL USE ONLY ~ The conclusion can be drawn from an.analysis of the timew~se structure of the development of a sliding spark that the character~stic of the break- - down which depends on the gap length (on tfie breakdown t~me) is character- ized by a range of flashover voltages falling between t~ao maximum cases (Figure 5, air, 1 atm). Curve 1 applies to the case of breakdown with a - single ("nonextinguishing") l.eader, which moves from one electrode to - the other without stopping. Curve 2, which occurs w~th lower values of the breakdown voltages, corresponds to leader development with stoppages. - The number of such stuppages exceded under our cond3tions. In this case, the flashover occurs at a minimum value of the voltage. In the first case, the average rate of leader travel is not too much different from the instantaneous value a~d amounts to 5- 8� 108 cm/sec, _ and in the second case, it is one to two orders of magnitude lower (from 1 5� 106 to 7� 10~ cm/sec). Thus, formula (1) determines the lower flash- over characteristic for the case of helium, neon and air, and the upper one in the case of argon. We will r.ote that to obtain a dense system of para11e1 discharges, the upper breakdown characteristic should be used. The hypothesis can be put forward,� in returning to the data of Figure 4, that a reduct3on in the influence of the pressure w~.th a decrease in the length of the discharge gap is rela~ed to the transition fxom multistage , breakdown to a single-pass flashover. I`n~the case of a single-pass flash- over in air, the excess volfiage of the.field at the head is rather high and the change in E/p w3th a change ~n p does nor influence the flash- _ - over development process. Tn hel~.um and neon, this influence is also not observed 3n the case of multipa~h breakdown. The analysis o� the set of data cited here from the point of view of the elementary processes makes it poss~.ble to explain the spec:Lfic features of flashover in argon by the presence of more powerful ion3zing rad3ation than in helium and neon. The specific features of breakdown in air are relaCed to its electronegativity and large thermal capac~ty, which leads � to a lower temperature and conductance (as compared to the ~,nert gases). ~ The authors would like to express their gratitude to V.P. Sidorova for ~ssisting in the work. ~ BBILIOGRAPHY 1. Andreyev, S.I., Zobov, Ye.A., Sidorov, A.N., "A Method of Controlling the Development and Generation of a System of Para11e1 Sliding Spark Channels in Air at Atmospheric Pressure", PMTF [JOURNAL OF APPLIED _ MECHANTCS AND ENGTNEERTNG PHYSTCS], 1976, No 3. 5 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-00850R040340020036-7 _ _:,;AL USE ONLY - 2. Andreyev, S.I., Zobov, Ye.A., Sidorov, A.N., F'A Study of a:.liding Spark in Air at Atmospheric Pressure", PM'~F, 1978, No 3. - 3. Toepler, E., "Stossspannung, Ueberschlag und Duzchs chlag bei Isolatoren" ["Shock Potential, Flashoyer ~nd Breakdown in the Case of Tnsulators"], E.T.Z., 1924, Vol 45, p 1024. 4. Strigel, R., in "Electrische Stossfestigkeit" ["E1e ctrical Breakdown - Resistance"], Springer Verlag Publishers, 1955. 5. "Tekhnika bol~shikh impul'snyich tokov i magnitnykh poley" ["Large Pui.~e _ Current and Magnetic Field Engineering"], Collection edited by Komel'kov, V.S., Moscow, Atowizdat Publi~hers, 1970. ~ _ 6. Roth, A., in "Hochspannungstechnik" [}'High Voltage Engineering"], Springer Verlag Publishers, 1959. 7. Sirotinskiy, L.I., Lomonosov, ~.I., Sergeyev, A.S., Panov, A.V., "Tekhnika vysokikh napryazheniy" j"Hi.gh Voltage Engineering"], Vol 1, GET PuDlishers, 1940. - 8.. Skhanavi, G.T. "Fizika d3elektrikov, Oblast} siltnykh poley" - ["The Physics of Dielect'rics. The Region of Strong Fields"], Moscow, Fizmatgiz Publishers, 1958. COPYR~GI~T : Tzdatel ~ stvo "NaukaF', F'ZIrurna1 prikl.adnoy mekhaniki i tekhnicheskoy fiz3ki", 1980. � [3144/1380-8225] 8225 CSO: 8144/1380 6 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 - FOR OFFICIAL USE ONLY UDC 537.523 HIGH--CURRENT COAXIAL DISC~iARGE IN THE AIR STABILIZED BY A DIELECTRIC WALL Moscow RADTOTEKHNIKA I ELEKTRONIKA in Russian Vol 25, No 6, 1980 pp 1218-1221 [Article by A. F. Aleksandrov, A. T. Savichev, O. I. Surov, I. B. Timofeyev, and A. R. Emil'] _ [Text] A continous emitting coaxial plasma sheath is produced by the electrical explosion of a vaporized metal coating ~epos- ited on a dielectric cylinder. Under certain experimental condi~ions the radiation of this discharge is close to equilib- _ rium with the temperature of the emitting surface ti2 eV. In recent years, high-current emitting discharges in atmospher- - ic elements and in air produced by electrical explosions of - thin metal wires have been investigated intensively [1] in re- - 5ard to their use as high-intensity radiation sources in the visible and ultraviolet regions. At the present time, emitting disc}iarges~. in the classical z pinch geometry [1) have been studie~ most thoroughly. However, linear discharges in spite of certain advantages, mostly in regard to the simple construction of such sources, have a small emitting surface and a relatively _ low resistanc~ to the deve lopment of superheating (transparent discharges) and power (opaque discharges) instabilities. _ Discharges with a return curr~nt [2] are more ~romising in this respect, especa,ally since the emitta.ng surface of such dischar- ges can theoretically be as large as needed, and the durati.on of the steady state can be i.ncreased b;~ a factor of R/r (R is the equili.brium radius o~ a discharge with a returnPcur-. rent, and r is the radius of a linear z pinch). Ho~rever, the - gPneration b~f a, .dense emitting plasma wii:h such a confa.guration presents some well-kno~tn difficulties. Thus, the formation of . such discharges by a simultaneous expl.osion of many wi.res [2] , - ~,n air for example, generally does not produce a single plasma sheath, but a discharge in the form of individual plasma chan- nels. 7 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000300024436-7 I~OK U[~ 1~ I t:1 A1, US~ ON1.Y A continuous emitting ~lasma sheath wa.th a~ai.rl,y large surface can prcbably be produced bx an el.ectrical ~xplosion of thin me- ta], foi~ or vaporized metal de~osited on a dielectri,c of arbi- trary sha~e (see [3] i.n thi.s xegard~ . Wox'king w~.th foil is difficult ~or purely techni.cal xeasons (it is d~ ffi,cult to con- struct a cylinder from tha.n foi.l with the correct shape) . The use of a metal deposited on a dielectx'ic cxlinder to induce a reverse pi.nch is technological].X advanced and ~resents certain advantages for a stationary inverse ~inch, since the pressure of the inner plasma boundazy is balanced by the dielectric wa11. The so-called H-pinch di.scharge is formed, and the ra- dius of the plasma sheath in it can be strictly controlled. In the present paper we investigate this type of discharge. (k V) K e - - , ..r.:.;~:~�'~~ '''~y"~,,4 - `'~Aw~�~: ZS ~~F~~~u, - ~Y ` � ~ � ~ iy . 7 . . ~ '.~lY~~ ~ ~ . ~ Y~ . � 1 ~Y .,f~'~ Y~ll~ s+ - : #?Ek; 0 p / I _6.. J 1 ~~.'.F"~:~ - ~ i 3 i ~ i p~ .re �t ' S, ' ~ a 0 ~ :?y. .t ~ ! 62S 2, based on the ~ sequential rotation of plar.e quasiconformal mappings, is considered. The method is used to derive the linear coefficients of quasiconformality of certain pairs of n-dimensional, n? 3, annular regions, as well as to obtain n-dimensional analogues of the corresponding theorems of distortion in the presence of q-quasiconfoxmal mappings of a 3-dimensional sphere onto itse].f. UDC 51.7.946 ~ THE DARBOUX PROBLEM AND A NONLINEAR HYPERBOLIC-PARABOLIC SYSTEM OF EQUATIONS IN A PLANE ORAZOV, L. [Text] The existence of a general solution of the Darboux problem for a system of nonlinear hyperbolic-parabolic equations is demonstrated. UDC 532.031 A CASE OF CONVERGENCE OF THE ITERATIVE METHOD AND ITS APPLICATION TO THE THEORY OF JETS PYKHTEYEV, G. N. [Text] A case in which the nonlinear operator A(u) of the equation u= ~ A(u) is a constant parameter), determined in Bana~h space, satisfies the Lipschitz condition in the sphere 0 X 10-1e Kr, ~ 146 ~ 2,5� 108 ~~u _ ~ I 3�10~ t~u) I43, 44]'> Ars, ~~Eu, 3~u~-?,YIEg l2Fi 108~~~4~: 10~ 1,5�10-ie~~> . ~ (~~u~ . Hez.. ~ I d3~4 i 63n~ I ~ I~ 10~ [46j - Hg, I Iu -.XOg I 335 I 4'5 10~ [47J . I ~.97� 10-1e [4T] XeF B(1/2}-.X(1/2) 353 (5,1[48,49]- (2[52]-5[53])X /B2E ~ X'zE ~ 351 -5,5 [50, 51 j) ~]0?; X 10-1e i ~/2 i/2 349 8�107[17.25] XeF ~ C(3/2} /t (3/2) I 470-480 I 6� 10� - lOT [25] I 5� 10-18 [ 132] _ KrF B(1/2)-.X(1/2) 249,5 .1.5~10" [23.54]; 6�10-'~ [57j: � 248,5 1�10a [55, 56j 2,7�10-1e [58J: 2~5, lp-ia (17] ~ ArF I. ~ s I 193 ( lOa [59]: 2�108 [24] I 2.9�10-1a [17j - XeCI I s ~ I307-308 9�10~ [25] I 4,5.1p-ls [17] KrCI I > > I ~ I - I - ArCI I s a I 175 I ' - ' I - XeBr I s I 282 I 5,7� l0~ [60] I 1,5. lp-t" (61 j KrBr I > > , I 206 ( ~ - I - Xe0 I ElE+-?B1E+ I538-544~ 10+" (62] I 10-19 [63] - Kr0 > > I 558 - I - I I ~ - Ar0 I > > I 558 I 2,6� 10� [62] I 2. lp-la [64] HgCI ( B~E~ ~2 X~E~ ( 558 I 4,5� lU~ ~[65] I 4.5� 10-16 (65~ 23 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 FOR OFFICIAL USE ONLY Table 1 (continuedj _ Moiecuy e I Tranp itA on I, nm) I MoneK na fTe eao xr A, c-~ a+, cw~ HgBr BzE~~2-.XzE~~2 502--504, 4.3�10' [66] 2,4�10-'~ [67] 498 HgJ I s ~ I443-~445I 3,7� 10' [66] I - t The effective values of A were found at rather high pressures . Typical times of r3diative decay of the lower states of R~ show con- siderable dependence on the density of the gas (see for example Ref, 39, 68-70). This is due mainly to strong collisional mixing of populations - of Ou and Iu [Ref . 71] . Many researchers feel that the upper laser s tate of R~ is Ou( lEu) alone. The following values were used in the estimation: A= 3�10~ s-1, ~wpasn - 0.5 eV jRef . 12] . - Under the same conditions, less intense lasing has been achieved - [Ref. 72] on other bound-bound transitions of He~: ap = 400, 403, 454 - and St3 nm. For excimers R~, the corrections Qb/o+ in (1) are due to photoionization. Usually photoionization can be disregarded as a consequence of the greater width of the photoionization band as compared with the photodissociation band. ThF~ problem of the ratio between the photoionization and photo- dissociation cross sections was qualitatively discussed in Ref. 73, According to calculations of Ref . 74, the cross section for photoioniza- tion of Ar~Eu at a= 126 nm is about 4�10'19 cm2, i. e. it is considerably less than the estimated [Table 1] photoionization cross section. Tran- sitions to repulsion or bound states lying above b are more likely than photoionization transitions. The effect that they have on the shape of _ the lasing spectra and gain is considerable for exciplexes that emit in the relatively lor~g-wave region. In Ref. 58, 7~, a continuous band was observed, and also a set of narrow absorption lines between the peaks (248.5 and 249.5 nm) of stimulated emis~ion of KrF*, belonging to tran- sitions from the working term to the covalent term, correlating with Kr*(3P) +F. In Ref. 28 the authors observed formation of highly excited atoms of Hg(73S1) accompanying laser photolysis o� HgX2 vapor. This was attributed to dissociative excitation of HgX*(B?E~) due to absorption of _ self-radiation. The authors of Ref. 76 used a similar argument to explain failure to achieve lasing on the proposed transition Ou -~0+ of the mercu- ry dimer (a = 485 nm) 1. g lIt can be concluded from Ref. 27 that there is no state Ou in the group of lower states of Hg~, and emission of the 485 nm band corresponds to phot4dissociative decay of trimers Hg~ rather than the dimers. 24 FOR OFFICIAI~ USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 I~Oh OI~FTCIAT, lIS}: ON1.Y Losses of amplified radiation determined by K~P will be briefly discussed ir~ Section 4. 2. Experimental Conciitions for Achieving Lasing Tables 2 and 3 give some data on experiments in w:iich amplification has been achieved on diatomic excimers and exciplexes. Since problems of organizing optical feedback are nonspecific for exciplex lasers, we have given information mainly that determines the properties of the active media. Brief explanations are given below. 2.1. Pumping method. The use of high-current relativistic (subrela- ~ tivistic) electron beams as the energy source is the most universall and groductive method of producing exciplex active media. Lasing (depending on the nature of the exciplex and a number of other factors) is realized - with the following typical beam parameters: electron energy "'0.1-2 Mev, current density ~6-103 A/cm2 (total current up to 150 kA), current pulse duration ^'2-1400 ns. Let us note that the capabilities of present-day electron beams are not restricted to these limits (see for example Ref . 182) , - Electric discharge methods are used to ex~.i~~ laser transitions corre- - sponding to large values of a~+ (RF*, HgX*): a ~�~lf-maintained trans- verse discharge (TE-lasers) and its modifications utilizing preionization (electric, light beam, electron beam, x-rays jRef. 151], radioisotope emission jRef. 183]); a discharge in the traveling wave mode (this tech- nique has been used to achieve amplification on ArCl* and KrBr* jTable 3J for which the Q.~ are relatively sma11); capacitive discharge jRef. 126]. Series electric-discharge lasers have been developed jRef. 184] that operate on XeF*, KrF* and ArF*. 1'he characteristics of exciplex electric discharge lasers can be widely varied by modifying the design, but their capabilities are limited by the development of instabilities with break- - down of dense gases (discharge pinching, arc ignition and so on). Arrangements for optical pumping of exciplexes [Ref. 185-189] were being discussed even be~ore the development of th~ first exciplex lasers. For a long time, this method was used to achieve lasing only on bound-bound transitions of R0, XeF, HgBr and HgCI. Recently amplification has been realized on the photodissociative transition C(3/2)-~A(3/2) of the molecule ~eF [Ref. 133, 134]. The possibility in principle of nuclear pumping of excimers and exci- plexes has been demonstrated in experiments [Ref. 85, 190]. When a nuclear charge is exploded, irtense superluminexcence of Xe~ is observed in nearby tubes containing dense xenon [Ref. 85]. Amplification in XeF* 1There is no basis for assuming that beam pumping is ineffective tn the case of KrBr*, Ar0* and HgI* since no serious attempts have been made to trigger lasers as yet by an electron beam in these exciplexes. - 25 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 FOI: OFFL"CIAI~ iJS~ ONLY ~~F ~ ~ o~ g y ~ ~ ~ ~ . - x ~ H - - ~ a ~ ~ zcSi~ u a ^ m.. O v G. ~ F a ~ t0 ~ ~ ~ J.J x w~~,��v ~ x s ct . ei a+ o ~ u a.~ 00 _ � ~ ~ a K d ~ A N P u~ sO1=ca c co ~-I H i ~ ~ o.~ a u ax,~ y I s v s 3 a ~ m~ s n.m d R ~ ai~ O a6 W N C t0 p, ~ x 71t u rl ~y d d' ~pp F( ` F ~ OC O 0 ~ ~ ~b e(o v K Go ~ ~ d~ W ~,V Ua~~+~ Cr, -~i ?~2u= 0~0 _ - ~ ~X ~ j ~ ~ Z ~ ~ ~ y ~ - ~ _ I I I I ~ ~ o ~ N u U1 % ~-1 - - fA GJ (n ~ N ~ ~q I T ~ ~ M ~ ~ ~ a - ~ wq ~ ~ ~ ~ o o ~ ~ al N rl "C U y ~ ~ rpq1 ~ Q m ~ ~ ~ ~ O Qi W Y R ~ ~ ~ ~ ~ H O e ~ O x a ~ ~ n~Y~ o iw p ~ c o 0 0 0 ~ . al 1fHN,~~ N ~ ~ - ~ c ,n ao G ~ r o g I i I t ~ ~ ~ a M ~ ~ ~ Z ~ a ~ ' N ~ O e'! d C ~ � O'~ 1 /~t ` ~ I t I fd ~ ~ v x : ~n ' $ ~ ~ N g N ~ r ~ ~ - - r-I e ~ q ~ U O �a ' q ~ O o 4-i I ,L~ ;Z , a O ~ O O 0 ~ O aD . . ~ O e ~i Z I i0 tD h ~ ~D O ao I ( ~ e'o � ~ ~ ~ ~ Vi ~ A ~ ~ G a~ o ~ t ~ y~.~ a ~ k y~ ~ ~ d ' ~ ~ ' ~ ~ ~e ~ x ~ ~e oe ~i w 0 U 26 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 i~c~ii ~~rH~icrni, usi~: ~~Ni,S~ I fy I ~ ~ CO OD Of ~ Of Q) yf S ~ .r ' ^ ~ l--- '=~s~ e s id =~'o ~ s~ ~ I I c~ u ~c Q~ ~ z c o` ^ ~ ~ T x~ o� : .~S~6b HF S~~ ~ ~Kyv ~X Qf J A o~05pp �Zl;~$~C S~ p CS ~ , ~~N= I x~ x~0 I ; I I n~ : ~ o�~~ a �J ~ s a ~I a ~ Q^p ~ ~O � ~ E: _ ~~d m~G ~ 4~,u " a eo e ~ QQU'' I O[.dCR.uG .OTFc~~~' M~yNy y~~j vS~ i~>.~p=O ~~OcC ai G p~ II~e', a4iOt~0 ~Oti = $~Cm~,~', UazR~' Cuv F+>, C:m�.. Cm- I I' i I I o I I I`,_�- , ~ , ~ - . I ~ ~ N I I I 1~ I _ o 00o RS X 0 ~ o - - g e~ cv t o cv ,d,' ~ N c4 ~ a ~ T~ - - p ~q I I I g o�- ~ o o 0 0 ~ - - - O o~,. � ~ o o o c p Y . ~ ~ ^Z ~ I!] ~ ( If ~ ) g ~ ~ ( N ~ n ~Y~ o ~ ~ ~ . ~ ~ ~H~YO I o; o I I o o , O o 0.1 H ~ - ~ - � I ~ ~ ~ d. m I ap O r u M ~ ~t. I ' Vl ~ I I I~,~ a i ~ o~ g p ~ o ~ ~ ~ p�~ ' t O I t` � ~Q ( ~ 2 t Q , i ~ N ~ ~ � I g � r ~ N w ~ ~ ~ O . ~ � . _ ~ o 0 c'~ e~ ~ o 0 0 ~ O 0 e O i ~ O O ~ C ~ o C � cD O1 N ' . n t, . ~ N ~ ~ I - N~ oq 'I ~ V '~i ~ .T. N ~ e ~ ~ ~ ~ v C ~ X -t' h~" ~C x .ag d ~o, vv aid~ v v ~ v d a ev x d~ xx xz� k x Q x~ x U 2~ FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 FOR OFFICIAL USE ONLY ~ a a ~n C io cD t~ a ~ �6 u ~ K ~ a o u s O ~ c x s � o ~ s o ~ F ~ a ~ ~t ~ Y = ~ - .SL ~ N a ~ ~ m U 0 i~+ = rl ~ ~ ~ ~ I N t~ ~ v ~ 'a = = ia GJ C x ~ t- =67 ~x= LY. ~~K~ ~v ~ o a+ ~ E" N s~a sp oum g Oxm Cma e c~ v _ ~ N I I. I I .c ~ ~ ~ I1.1 ' C ll) ~ o . ~ ( o g O _ x ~ = p tf~ ~r~i I J If~ ~ ~ I C~`I ~d ~-i ~ y~ ~ ~ ~ ~ ~ ~ w a a w ~ Y .r Q~ ' Tl . ~'i ti Y O Ol G I O ~ I ~ I~ ~ r..~ V ~ ~ V Y V~ ~ UT n ~ ~ ~ a ~ a daxi axi ~ ~ a~ o o ~ ~o ~ I ~ ~ y Yv ~ o o , i ~ ~ ~ ~ ~ g .~G F ~ i t ~ ~ i' ~ a" I I g' ~j �u , w : ~ ~ g g o - .am I I t ~ t o ~ ~ ~ ~ ~ I ~ M ~ ~ - M ~ ~ a . ~ ~ 1 ~ w O O i 1 ~ ~ ~ ~ O o el � w - ~ a ~ O e. O ~ r ~ - ~ ~ h O ~ ~ ~ O ~ v ~ CO . M R' y,l - ~J k a ~ ~ ~ o ~ . O U ~C .~1L ~ ~ Tr ~ 2V ~ FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 FOR OFFICIAL USE ONLY Explanation of column headings for Table 2: N--density of particles of the medium, cm 3 ip, Q--pumping duration and specific power, ns and M~~7/cm3 ~T, r--amplification delay and duration, ns ~~`cna ~~`HHA--bandwidths of spontaneous and induced emission respectively WnHH--Peak power, kW en- energy of laser radiation, J - L--length of the active region, cm K--gain, cm 1 p~p--efficiency of energy conversion in the medium, % T--gas temperature Numbers in parentheses show authors' estimates of K. An electron beam was used as the pumping source everywhere except Ref. 85. Key to translation of remarks in Table 2: ' 1--Angular divergence less than 5 mrad 2--Laser radiation energy is increased with the addition of argon; maximum gain is realized at higher pressures 3--The resonator mirror was burned through 4--Ribbon beam S--Optimum particle density for Xe is N= 4.7�1020 cm 3; maximum peak power is not attained in mixtures 6--The pumping source was gamma radiation of a nuclear explosion; ampli- fication was not observed at N< 2.8�1020 cm 3 7--Lasing intensity falls off with increasing gas temperature; mixtures are more efficient than pure Xe 8--At Tp = 2.5 ns the lasing intensity is lower for mixtures, and at Tp = 50 ns it is greater for the mixtures than for Xe 9--Tuning of wavelength over a range of 169.5-174.5 nm 10--Tuning of wavelength over a range of 169-175 nm 11--Gas purity 99.99% 12--Purification of gas after each pulse increases laser output _ 13--Linear increase in peak power with increasing particle density 14--The position of the maximum in the spectrum depends on pressure was achieved in Ref. 190. A tube containing a mixture of NF3-Xe-Ar covered inside with a thin layer of boron (isotope 10B) was exposed to a . neutron flux from a pulsed reactor. The direct source of pumping energy was the nuclear reaction 10B(n,a)~Li. In Ref. 191 a proton beam was first used to stimulate an exciplex laser - transition. Here are some of the characteristics of this laser: proton energy ~^450 keV, current density ~^10 A/cm2, -rp S~) ns, mixture NFg:Xe:Ar = 1:5:194, p~^ 1 atm, Q> 1.5 MW/cm3, T~^ 10-20 ns, en up to ~^0.05 J, L~' 7.5 cm, K< 0.052 cm 1, n~P up to 2.7%. 29 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 FOR OFFICIAL USE ONLY ~~y Cz1$xo~F XGUUU ~~a ~~M=xS~ p~~ - - ~ o;! ~ ~ o o Z ~ o ~ I I ~ F ~ ~D X~~ I I I i I 1 I I I I I � ~ ~ . ~ ~ n ~ � l ~ I I N, _ ~ - - - � q I o c~ : ~n o, ~ o o m ~n o a ^ - a " . 0 o cr o 0 0 - ~ _ G o . . . . � . ~ y o 0 0 0 1N o 0 ~ q~ ~ ~ ~ N ~ ~ ' o ~ ~ ~ i . ~ - ti C~+' a'2 Y ~ ~ ~ - ~ I _ O o 0 = U = ' O b ~ c~ ~ ~ ~ ~ ~ ~'i 1!! ~ V ~ M ~ ~ ~ ~ ~ ~ F' I I I I I I I I I I 1 I r o C ~ - - ~ ~ a j ~ ( ~ ~ t ~ ( ~ ~ ~ ~ ( ~ _ GC 2 ~ 0 _ ~ 1p I 1n cY ~i CV O o I I I O _ y il ~ A ~ _ . ~ m N . T t1+p7 ] Y 1A - N {7 GV ~ ~ ~ ~ lf C ~ I ~ I G _ 0 ~ ~ O O ~ O ~ O - O N O ~ n O ~ ~ N p N ~ O ~ V` ~ K ~ m ~ u'f N~ N p ~ ~ ~ L V O [r O^ N f^j N p o ~ 'Cn e a ~ y I~ ~ ~ y u'.o~^. I ~ ~ ly ~ ~ ~ I ~ 0 4 ~ C - ~ o ~ d u ai y e; x I y ai 0 U u >C YC ~ n }C ~ a, ~ X iC V r ~ Yo - U ~C U K I (`j "J % n w 6 Mw~ G w C m ^ m w m m m a C qo~uu~ fq ~y f- F G F a F k~ a Cq uFdmna 38 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 I~t)It c)~~1~?c:inl, Usl~, c~NI,Y ~ � ^ v Bd,t~ ~ ~ ~ = ~ ~ ~ �QdatH~~ ~ J_ _ q= o a- a = m Y xo't~i~m3. z== R A T~ dl'~i c'. = 4C a~ (n = QYxF ud Coy~ O a~p,"m~S~D ~ ~ ~ 'O^`u 3E I ~ ~ I I _ ~ x 01 a ~ m m ot F~ - d~3. Q" o S n ~ ~ G L R ~ U u U d L d 6~ ~ d f A ~ a~r,a.p=o SKUx ~ y1LSpp{~`6 OTOC ~=sT x~ K CCxu ...uC Y-~~I+.C ~e N ' O i I I I' I I I I - ~ o ~ - = ~ � I I i ~ I I � ~ ~ � X= o 0 0 . ~ - - - - - ~ ~ o ~ ~ N ~ ~ = I ~ ~ _ - ~ * o ~ ~ I ;I ~ ex r. . I o 0 0 0 _ . o . � a K o 0 ~ o ~ , qQ ~ ~ ~ i�a `p ! o' ~ o ~ ^ ~ 3Y ` - ~ _ _ _ ~ ` G ~i � p L u~ a 1 ~ ~ m t o < ~ e>C i I I .u m ~ r m a ~ T T U Y eYi 61 y ~i. _ ~ ~ O ~ ~ ~ _ N A _ ~ O O Z I ~ I I ~ r _ ~ G E~ u ~ I I ~ ~ Z:~ ,/t, .o,~ 2 2 ~ - - - - - u c o ~ ~ I co ~�n~ il �w x I � : ~ _ _ ~ - n x ~ j o, I r; j ~ I : ~ ' � ~ ~ 2 n o ~ o , ~ p O O ~ = O O O ~ n h O ~ ~ c0 Q,~ t0 1D p N' ^ 'r~ tj ~ p p O c+ I ~ O ~ yJ Y M ~ ~j U~ p1 O O V II D �Iu 6! ~Y W O ~ ~ p, ~ x a a x x x II ~d ~ pU K X' ~ x x 4 4 K K i� ~ U ~ U U U x U U ~ ~ ~ l~~eiMip W G G. W a t~a m m~m R~i ~N~~ m m a Q a u~daTn 39 FOR OFFICIAL L'SE OA1LY - APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 1~ULt Ul~t~l(:IAL U5L UNLY ~ ~ ^ ^ ^ _ ( ^ c r1 ri i a~ o c~ ~y ~ ( ~trd~ia~; ~ : ~ ~ ~ " :y ~ ~ S~m`a�~Y' �~~~c - ~o=xx=yW s q~T. u~ `'mam~ u~ x o-0a're~i=Cu� ~ ~ ~ do rx~ ~uUL ~ a2-~socoi~o ~ oF ~FV U_ u _ ~~=aox ~ o~2~=a~ G am=aau ~ da~i~~ I ~ `.G SC mc~+ �u=Yn I I ~ ~y R h 6! y L ZQto S`-' qmSi9e(5 ~ O O m~~Sp I 'Y ~ =~~Y~u U ~3ac~ h .A.. ~ Y~=p ~OS ~su=OY NZ~.a~.A II Y II ~�a~I ti7r,= ~ a Kx~O u ~CUri tC 4 .i 1. h S KfO u c=i Yti 7 I p ~ ( ~ ~ ~ ~ ~ ~ . _ ~ N V7 b N ~ W y ~ ; ~ Q C'1 p X'~ I I I O O O p O ~ O ~ O O rj ~ ~ ~ ~ ~ ~ 7 ~ N . N I O O O O ' O J ~ . a0 00 h ~ p p ~ ~ , ~1 p ~ O O . ^ , ~ ~ ' O I ~ N ~ I ~ ~r, ~ ~ ~ O O ~ O ~ O O I 1 O I I i I I ; bd.' ~ s Nl ~ ~ - - y � ~ p o o a, d ~ o . u Y N ~ ~ I }C ~ ~ ~ O ~ ~ W I ~ o0 ~ S . ~ ~ m ~ a o y ~ ~ ~ ~ C)A ~ ~ q ax. N u _ ~ ~ o G - - - o o - ,a `r ~ ~ � o ''F'"' ~ � - ~ r C~V ~ ~ ~ ~ C' ~ I ~ ~ O H ~f co 2 ,�Q ~ ? '4 ~n N N ~ N _ ~ ~ _ ~ ~ . a~ ~ ~ '~P , ~ ~ I I I � I ~ l. I . I ~ ~ ~ O Y ~ ~ ~ ~ I I N ~ m I ` 2 s ~ - - ~ ~ ~ ~ ~ ~ o ~ w ~ ~ Z ~ _ u' - _ ~v ~ I . . ~ - X - ~ a r o c~ . `,r~ i -f- ~ ; . ~ _ o . ~ O v~i ~ ~ ~ Z., C:. a P~ ~ ~ II a;; ~ ~ ~ ~ f:; = u ~ ~ ~ � � l.~ .:~i a d ai Y, a~ I- F' ' i I X f iC iS ~ c, O� G 4 i m nt ~ = O O C� = s = - s x - x � z z zc $ -~f ~TT'~ ~ - - - - - - ~~r~,~:Nry . ~ 1.. (J J! 1 l l � ~ .r. x .T. .T. ~,ut~:u;:~,i a m a m o 0 0 ~ p 40 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000300020036-7 APPROVED FOR RELEASE: 2007102/08: CIA-RDP82-00850R000300020036-7 ~ I~Ofl ~~FTCIAL (1St~ ~NLY w ~ ~ v ~ ao ~n n ai ~ a Ba~, ~ _ ~ ~ ti y y m �@dilNjf r I ~ ~ ~ y ~ ~ ~ _ = V 6 y C Y/1 O'~ Q. ~ C ~i1 ~ 1�a00 t~! Y~ e'70 S = p ao = a r~ S a`O S mv II �~n x m eC ~l! K F R~C T, = Y ~ ~ ~ a a' 4 m~ ~ _ ~ U U= U ~j c= d a07 o aGi U�� N = o o tD o o �i o'^ - ~ o 0 C1 C c`Li c~v w e~ ..~i s c r. d�, S u�i'~ S ~n ci ~o ^i a+ II il'~" II II A oon hs` ~~m ~s~ ~~iOOo t-. Il ~ h A t( n c k ~ ti m 4 il w,n ' a Q,~ Y] O O M I N I F o 0 0 0 o r~ X~_ ~ ~ ~ ~ ~ ~ ~ ~ ~ u 1 ~ ~n ~ v o o ^ o ~ - ~ r ~o ~ a S - - ~ ~ I ~o I �o '�o I I I�- j - - o 0 K o o ro n .c N 4m f ~ ~ ~ ~ ~ b ~ ~ ~ Y ~ ~ ' _ ~i v U f0 ~ ~ ~ O W O W I W x I N 1D ! ~i Y m A S V Y Y v d ~ ~ Y ~ G S ~ ~ ~ ~ ~ S O O ~ r ~ .r p N I I I n 1 m a H : ~ o,~ ~ I I 1 n I ? 1 I _ i l U S O O O O O O O O ~ . v~ w o o a ~ v~ ~ n : ~ v~ M ~ ~ ~ ~ .e ' n a F ~ N N ~ l7 e ~ ~ t z,~ g o - 0 _ o 0 ~ � ~ o~ y~,~ a yI ~p U o ~ +0' ~ ~ r' ~i ~o N: 4���� Q m eri k2a is the coef- ficient of attenuation of the wave due to scattering in the Born approxi- mation. Thus the size of the inhomogeneities must be much smaller than _ - a wavelength, and the attenuation of the wave due to scattering at the distance equal to the size of the inhomo~eneities must be small. Let us write the integral equation for the MCF of the emission as ~ T(R. P) = A f dZR' f dzP~r (R~~ P~) P lR~ -i- 2 P~ I P I R' - 2 p'1 X / \ 1 _ X exp 2F R'p' Iexp f~Z (R - R') (P - p')J X \ / L X exp - 4n=kaL ~ dt ~ dKK~U (K) (1 i- !o (I P~ -f-~P - P~) t ~ K)~1, ~2~ - 0 ~ where p is thP reflectivity of the mirrors over the field, F is the radius of curvatiire of the mirrors, and L is the distance between them. We - disregard effecte associated with the fact that the radiation after - ref~ection frotn the mirror passes through the same inhomogeneities, - which is permissible when L/k�a2. The index of the next to last expo- nential function of the kernel of integral equation (2) can be repre- sented as (p=-!-pp'+p'=), where q=